[uggrid] Support for transferring element data during load balancing

dune/grid/common/datahandleif.hh

@@ -165,18 +165,6 @@ namespace Dune
       CHECK_AND_CALL_INTERFACE_IMPLEMENTATION((asImp().scatter(buffIF,e,n)));
     }
 
-    /**
-     * \brief update after grid changes
-     *
-     * This method is called during load balancing after `gather` and any
-     * grid changes and before `scatter`.  It should be used to update
-     * mappers so that data received during the `scatter` phase will be
-     * stored in the right location.
-     *
-     * The default implementation is a no-op.
-     */
-    virtual void update() {}
-
   private:
     //!  Barton-Nackman trick
     DataHandleImp& asImp () {return static_cast<DataHandleImp &> (*this);}